Sub-Personas are a cornerstone of character customization and combat strategy in Persona Q2. Each character can equip one Sub-Persona in addition to their Main Persona. Sub-Personas grant additional HP and SP, and more importantly, provide access to a secondary set of skills. This allows you to cover elemental weaknesses, add healing capabilities to an attacker, or give a support character offensive options. The skills a Sub-Persona grants are determined by its level and innate abilities. Experimenting with different Sub-Persona combinations is vital for optimizing your party.
Skill Cards are another powerful customization tool. These consumable items allow you to teach specific skills to any equipped Persona (Main or Sub). Skill Cards are obtained through various means, including treasure chests, quest rewards, and by sacrificing Personas in the Velvet Room. This system allows for incredible flexibility, letting you tailor your Personas' skill sets to perfectly complement your party's strategy. For example, you can teach a powerful healing skill to a Persona that doesn't naturally learn it, or give an elemental attack to a physical attacker to help them hit weaknesses. Strategic use of Skill Cards can turn the tide of difficult battles.